127828721 has 2 divisors, whose sum is σ = 127828722. Its totient is φ = 127828720.

The previous prime is 127828711. The next prime is 127828759.

127828721 is nontrivially palindromic in base 10.

It is an a-pointer prime, because the next prime (127828759) can be obtained adding 127828721 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 115261696 + 12567025 = 10736^2 + 3545^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 127828721 - 2¹⁴ = 127812337 is a prime.

It is not a weakly prime, because it can be changed into another prime (127828711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63914360 + 63914361.

It is an arithmetic number, because the mean of its divisors is an integer number (63914361).

Almost surely, 2^127828721 is an apocalyptic number.

It is an amenable number.

127828721 is a deficient number, since it is larger than the sum of its proper divisors (1).

127828721 is an equidigital number, since it uses as much as digits as its factorization.

127828721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25088, while the sum is 38.

The square root of 127828721 is about 11306.1364311599. The cubic root of 127828721 is about 503.7435300168.

The spelling of 127828721 in words is "one hundred twenty-seven million, eight hundred twenty-eight thousand, seven hundred twenty-one".